There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ ln(cos(\frac{1}{x}))\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( ln(cos(\frac{1}{x}))\right)}{dx}\\=&\frac{-sin(\frac{1}{x})*-1}{(cos(\frac{1}{x}))x^{2}}\\=&\frac{sin(\frac{1}{x})}{x^{2}cos(\frac{1}{x})}\\ \end{split}\end{equation} \]

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